Question

The ΔHcomb value for anethole is−5539kJ/mol. Assume 0.900g of anethole is combusted in a calorimeter whose heat capacity (Ccalorimeter ) is 6.50kJ/°C at 20.6°C. What is the final temperature of the calorimeter?

a. 24.6°C
b. 28.3°C
c. 31.1°C
d. 33.8°C

Answer 1

To find the final temperature of the calorimeter, calculate the moles of anethole, determine the energy released upon combustion, and then use the calorimeter's heat capacity to find the temperature change. Finally, add the change to the initial temperature to get the final temperature.

Step-by-step explanation:

The student is asking about the change in temperature of a calorimeter resulting from the combustion of a known amount of anethole. The ∆Hcomb value given for anethole is –5539 kJ/mol. To find the final temperature, we'll use the heat capacity of the calorimeter and the mass of anethole burned.

To calculate the energy released during the combustion, we first need to find the moles of anethole:

1. Calculate moles of anethole: Moles = mass (g) / molar mass (Molar mass of anethole).
2. Calculate the energy released: Energy (kJ) = moles × ∆Hcomb (kJ/mol).
3. Using the calorimeter's heat capacity, determine the temperature change: ∆T (°C) = Energy (kJ) / Ccalorimeter (kJ/°C).
4. Add the temperature change to the initial temperature to find the final temperature.

Without the molar mass of anethole provided, we cannot complete this calculation exactly. However, once the molar mass is known, the steps above can be followed to determine the final temperature of the calorimeter.